A Dissertation Submitted in Partial Fulfillment of the Requirement for Award of the Degree of Master of Laws, (LLM) - of Mzumbe University.This study examines the effectiveness of Parliament in the controlling over delegated legislation in Tanzania, specifically the parliamentary Subsidiary Legislation Committee. The problem addressed in the study is that, despite the parliament having been empowered by the Constitution of United Republic of Tanzania to delegate its legislative power to executive authorities to enact subsidiary legislation, little has been done by the law to ensure the proper legislative control over delegated legislation, a case which result to inconsistencies in laws and practice. The study is mainly based on primary data collected through review of literary works and questionnaire given to selected personalities. The result of the study reveals that Parliament delegates its legislative power to the executive authorities and granted itself an obligation to oversee authorities without enacting a law which will empower the organ to do so. This is to say there is no hard and fast rule which bind executive authorities to stick fast to the Act of parliament while making of delegated legislation as a result the authorities fails to adhere to the procedure stipulated under the law. The study also revealed that the confusion of parliament as to which procedure to follow in the control of delegated legislation is caused by the parliament itself as it enacted various provision with various procedures for making of subsidiary legislation in Tanzania. This made the organ to play little role in the control of delegated legislation in Tanzania. It is therefore recommended that there is a need for parliament to restructuring on the issue of control of delegated legislation in Tanzania by increasing much power and provide uniformity procedures to allow parliament and its committee to watch on delegated legislation properly. Parliament should enact single legislation which provides for parliamentary control over delegated legislation in Tanzania. Last capacity building is required for Members of Parliament to be able to oversee legislation properly; they should be in a position to understand the power they delegate and the effect brought by abuse of such power. By so doing the organ will play its role effectively.